United States patent application publication No. US2005/0068382A1 describes an ink cartridge housing an ink bag. A valve is attached to the ink bag. When the user mounts the ink cartridge into the recording device, an ink supply needle provided in the recording device opens the ink bag valve, allowing ink in the ink bag to be supplied to the recording device through the ink supply needle.
United States patent application publication No. US2005/0212874A1 describes an inkjet printer, in which a subsidiary tank is provided between a main tank and an inkjet head. The subsidiary tank is for separating air from ink and for generating a desired pressure head difference between the inkjet head and the subsidiary tank.